BRIEF REPORT Detection and characterization of porcine caliciviruses in Italy Ilaria Di Bartolo • Silvia Tofani • Giorgia Angeloni • Eleonora Ponterio • Fabio Ostanello • Franco Maria Ruggeri Received: 29 January 2014 / Accepted: 31 March 2014 / Published online: 1 May 2014 Ó Springer-Verlag Wien 2014 Abstract Porcine noroviruses and sapoviruses have been sporadically reported in European countries, and more rarely in Italy. In this study, stools samples were collected from both asymptomatic and diarrheic pigs from northern Italy and were screened for caliciviruses by RT-PCR. Sapoviruses were detected frequently and were genetically related to both the GIII reference strain and the newly described porcine sapovirus genogroups. Porcine norovirus was detected in one asymptomatic pig (0.5 %) and was genotyped as GII.11. This is the first detection of porcine norovirus in Italy. Keywords Sapovirus Á Norovirus Á Zoonoses Á Porcine Sapoviruses (SaVs) and noroviruses (NoVs) are emerging enteric pathogens of humans and animals, forming two separate genera in the family Caliciviridae. Both are small (27–40 nm) non-enveloped viruses containing a positive- sense single-stranded RNA genome of approximately 6.5–7.5 kb. Presently, norovirus is recognized as the most important cause of non-bacterial epidemic human gastro- enteritis worldwide, affecting both adults and children [27]. Human sapovirus infections occur less frequently than norovirus infections and mainly affect children under 5 years of age [21]. SaV and NoV have been described in many industrialized and developing countries and different animal species [16, 18]. Genetic analyses have shown that some calicivirus animal strains are closely related to human strains [24, 25], suggesting that they may be a potential risk for zoonotic transmission to humans. Noroviruses are subdivided into five genogroups [27]. Porcine noroviruses (PoNoVs) are genetically related to human strains and are classified within GII, which includes most of the strains causing epidemics in humans. Porcine NoVs belong to genotypes GII.11, GII.18, or GII.19, all of which have been identified only in pigs [27]. Noroviruses have been detected in finisher swine, while SaVs have been reported in pigs of all age groups [25]. Furthermore, NoV infections in swine are asymptomatic [26], whereas SaVs can either infect animals asymptomatically or cause diar- rhea [3, 7, 16, 18], alone or in association with other viruses such as rotavirus [11]. Sapoviruses are divided into seven genogroups (GI– GVII), each further subdivided into several genotypes or genetic clusters [24]. The majority of porcine SaVs resemble the prototype GIII PEC-Cowden strain [2]. However, the group of porcine SaV (PoSaV) was recently broadened, highlighting a higher genetic heterogeneity than was previously recognized [24]. The established PoSaVs now include GIII, VI, VII, and VIII strains [7, 16, 24], and the recently proposed novel genogroups GIX? and GX? [8, 11, 16]. The high genetic divergence of porcine SaV strains was further confirmed by the analysis of complete capsid sequences, which led to the recognition of 14 different genogroups [18]. In Italy, PoSaVs infections have been reported in both asymptomatic and diarrheic pigs [11, 16]. In contrast, the presence of NoVs in pigs has not been reported previously. In this study, the prevalence of NoV and SaV infections was investigated by analyzing fecal samples collected from I. Di Bartolo (&) Á S. Tofani Á G. Angeloni Á E. Ponterio Á F. M. Ruggeri Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanita `, Viale Regina Elena 299, 00161 Rome, Italy e-mail: ilaria.dibartolo@iss.it F. Ostanello Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, BO, Italy 123 Arch Virol (2014) 159:2479–2484 DOI 10.1007/s00705-014-2076-5